Complete the (mechanical) move of the TCP reassembly and timewait

functions from their origininal place to their own files.

TCP Reassembly from tcp_input.c -> tcp_reass.c
TCP Timewait   from tcp_subr.c  -> tcp_timewait.c

5 files changed, 23 insertions, 624 deletions

diff --git a/sys/netinet/tcp_input.c b/sys/netinet/tcp_input.c
index ad42e03..6fcbded 100644
--- a/sys/netinet/tcp_input.c
+++ b/sys/netinet/tcp_input.c
@@ -134,29 +134,6 @@ SYSCTL_INT(_net_inet_tcp, OID_AUTO, insecure_rst, CTLFLAG_RW,
     &tcp_insecure_rst, 0,
     "Follow the old (insecure) criteria for accepting RST packets");
 
-SYSCTL_NODE(_net_inet_tcp, OID_AUTO, reass, CTLFLAG_RW, 0,
-    "TCP Segment Reassembly Queue");
-
-static int tcp_reass_maxseg = 0;
-SYSCTL_INT(_net_inet_tcp_reass, OID_AUTO, maxsegments, CTLFLAG_RDTUN,
-    &tcp_reass_maxseg, 0,
-    "Global maximum number of TCP Segments in Reassembly Queue");
-
-int tcp_reass_qsize = 0;
-SYSCTL_INT(_net_inet_tcp_reass, OID_AUTO, cursegments, CTLFLAG_RD,
-    &tcp_reass_qsize, 0,
-    "Global number of TCP Segments currently in Reassembly Queue");
-
-static int tcp_reass_maxqlen = 48;
-SYSCTL_INT(_net_inet_tcp_reass, OID_AUTO, maxqlen, CTLFLAG_RW,
-    &tcp_reass_maxqlen, 0,
-    "Maximum number of TCP Segments per individual Reassembly Queue");
-
-static int tcp_reass_overflows = 0;
-SYSCTL_INT(_net_inet_tcp_reass, OID_AUTO, overflows, CTLFLAG_RD,
-    &tcp_reass_overflows, 0,
-    "Global number of TCP Segment Reassembly Queue Overflows");
-
 int	tcp_do_autorcvbuf = 1;
 SYSCTL_INT(_net_inet_tcp, OID_AUTO, recvbuf_auto, CTLFLAG_RW,
     &tcp_do_autorcvbuf, 0, "Enable automatic receive buffer sizing");
@@ -181,8 +158,6 @@ static void	 tcp_dropwithreset(struct mbuf *, struct tcphdr *,
 		     struct tcpcb *, int, int);
 static void	 tcp_pulloutofband(struct socket *,
 		     struct tcphdr *, struct mbuf *, int);
-static int	 tcp_reass(struct tcpcb *, struct tcphdr *, int *,
-		     struct mbuf *);
 static void	 tcp_xmit_timer(struct tcpcb *, int);
 static void	 tcp_newreno_partial_ack(struct tcpcb *, struct tcphdr *);
 static int	 tcp_timewait(struct inpcb *, struct tcpopt *,
@@ -213,192 +188,6 @@ do { \
 	    (tp->t_flags & TF_RXWIN0SENT) == 0) &&			\
 	    (tcp_delack_enabled || (tp->t_flags & TF_NEEDSYN)))
 
-/* Initialize TCP reassembly queue */
-static void
-tcp_reass_zone_change(void *tag)
-{
-
-	tcp_reass_maxseg = nmbclusters / 16;
-	uma_zone_set_max(tcp_reass_zone, tcp_reass_maxseg);
-}
-
-uma_zone_t	tcp_reass_zone;
-void
-tcp_reass_init(void)
-{
-
-	tcp_reass_maxseg = nmbclusters / 16;
-	TUNABLE_INT_FETCH("net.inet.tcp.reass.maxsegments",
-	    &tcp_reass_maxseg);
-	tcp_reass_zone = uma_zcreate("tcpreass", sizeof (struct tseg_qent),
-	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
-	uma_zone_set_max(tcp_reass_zone, tcp_reass_maxseg);
-	EVENTHANDLER_REGISTER(nmbclusters_change,
-	    tcp_reass_zone_change, NULL, EVENTHANDLER_PRI_ANY);
-}
-
-static int
-tcp_reass(struct tcpcb *tp, struct tcphdr *th, int *tlenp, struct mbuf *m)
-{
-	struct tseg_qent *q;
-	struct tseg_qent *p = NULL;
-	struct tseg_qent *nq;
-	struct tseg_qent *te = NULL;
-	struct socket *so = tp->t_inpcb->inp_socket;
-	int flags;
-
-	INP_LOCK_ASSERT(tp->t_inpcb);
-
-	/*
-	 * XXX: tcp_reass() is rather inefficient with its data structures
-	 * and should be rewritten (see NetBSD for optimizations).  While
-	 * doing that it should move to its own file tcp_reass.c.
-	 */
-
-	/*
-	 * Call with th==NULL after become established to
-	 * force pre-ESTABLISHED data up to user socket.
-	 */
-	if (th == NULL)
-		goto present;
-
-	/*
-	 * Limit the number of segments in the reassembly queue to prevent
-	 * holding on to too many segments (and thus running out of mbufs).
-	 * Make sure to let the missing segment through which caused this
-	 * queue.  Always keep one global queue entry spare to be able to
-	 * process the missing segment.
-	 */
-	if (th->th_seq != tp->rcv_nxt &&
-	    (tcp_reass_qsize + 1 >= tcp_reass_maxseg ||
-	     tp->t_segqlen >= tcp_reass_maxqlen)) {
-		tcp_reass_overflows++;
-		tcpstat.tcps_rcvmemdrop++;
-		m_freem(m);
-		*tlenp = 0;
-		return (0);
-	}
-
-	/*
-	 * Allocate a new queue entry. If we can't, or hit the zone limit
-	 * just drop the pkt.
-	 */
-	te = uma_zalloc(tcp_reass_zone, M_NOWAIT);
-	if (te == NULL) {
-		tcpstat.tcps_rcvmemdrop++;
-		m_freem(m);
-		*tlenp = 0;
-		return (0);
-	}
-	tp->t_segqlen++;
-	tcp_reass_qsize++;
-
-	/*
-	 * Find a segment which begins after this one does.
-	 */
-	LIST_FOREACH(q, &tp->t_segq, tqe_q) {
-		if (SEQ_GT(q->tqe_th->th_seq, th->th_seq))
-			break;
-		p = q;
-	}
-
-	/*
-	 * If there is a preceding segment, it may provide some of
-	 * our data already.  If so, drop the data from the incoming
-	 * segment.  If it provides all of our data, drop us.
-	 */
-	if (p != NULL) {
-		int i;
-		/* conversion to int (in i) handles seq wraparound */
-		i = p->tqe_th->th_seq + p->tqe_len - th->th_seq;
-		if (i > 0) {
-			if (i >= *tlenp) {
-				tcpstat.tcps_rcvduppack++;
-				tcpstat.tcps_rcvdupbyte += *tlenp;
-				m_freem(m);
-				uma_zfree(tcp_reass_zone, te);
-				tp->t_segqlen--;
-				tcp_reass_qsize--;
-				/*
-				 * Try to present any queued data
-				 * at the left window edge to the user.
-				 * This is needed after the 3-WHS
-				 * completes.
-				 */
-				goto present;	/* ??? */
-			}
-			m_adj(m, i);
-			*tlenp -= i;
-			th->th_seq += i;
-		}
-	}
-	tcpstat.tcps_rcvoopack++;
-	tcpstat.tcps_rcvoobyte += *tlenp;
-
-	/*
-	 * While we overlap succeeding segments trim them or,
-	 * if they are completely covered, dequeue them.
-	 */
-	while (q) {
-		int i = (th->th_seq + *tlenp) - q->tqe_th->th_seq;
-		if (i <= 0)
-			break;
-		if (i < q->tqe_len) {
-			q->tqe_th->th_seq += i;
-			q->tqe_len -= i;
-			m_adj(q->tqe_m, i);
-			break;
-		}
-
-		nq = LIST_NEXT(q, tqe_q);
-		LIST_REMOVE(q, tqe_q);
-		m_freem(q->tqe_m);
-		uma_zfree(tcp_reass_zone, q);
-		tp->t_segqlen--;
-		tcp_reass_qsize--;
-		q = nq;
-	}
-
-	/* Insert the new segment queue entry into place. */
-	te->tqe_m = m;
-	te->tqe_th = th;
-	te->tqe_len = *tlenp;
-
-	if (p == NULL) {
-		LIST_INSERT_HEAD(&tp->t_segq, te, tqe_q);
-	} else {
-		LIST_INSERT_AFTER(p, te, tqe_q);
-	}
-
-present:
-	/*
-	 * Present data to user, advancing rcv_nxt through
-	 * completed sequence space.
-	 */
-	if (!TCPS_HAVEESTABLISHED(tp->t_state))
-		return (0);
-	q = LIST_FIRST(&tp->t_segq);
-	if (!q || q->tqe_th->th_seq != tp->rcv_nxt)
-		return (0);
-	SOCKBUF_LOCK(&so->so_rcv);
-	do {
-		tp->rcv_nxt += q->tqe_len;
-		flags = q->tqe_th->th_flags & TH_FIN;
-		nq = LIST_NEXT(q, tqe_q);
-		LIST_REMOVE(q, tqe_q);
-		if (so->so_rcv.sb_state & SBS_CANTRCVMORE)
-			m_freem(q->tqe_m);
-		else
-			sbappendstream_locked(&so->so_rcv, q->tqe_m);
-		uma_zfree(tcp_reass_zone, q);
-		tp->t_segqlen--;
-		tcp_reass_qsize--;
-		q = nq;
-	} while (q && q->tqe_th->th_seq == tp->rcv_nxt);
-	ND6_HINT(tp);
-	sorwakeup_locked(so);
-	return (flags);
-}
 
 /*
  * TCP input routine, follows pages 65-76 of the
diff --git a/sys/netinet/tcp_reass.c b/sys/netinet/tcp_reass.c
index bff1e01..2cb9b69 100644
--- a/sys/netinet/tcp_reass.c
+++ b/sys/netinet/tcp_reass.c
@@ -30,28 +30,20 @@
  * $FreeBSD$
  */
 
-#include "opt_ipfw.h"		/* for ipfw_fwd	*/
 #include "opt_inet.h"
 #include "opt_inet6.h"
-#include "opt_ipsec.h"
-#include "opt_mac.h"
 #include "opt_tcpdebug.h"
 
 #include <sys/param.h>
 #include <sys/kernel.h>
 #include <sys/malloc.h>
 #include <sys/mbuf.h>
-#include <sys/proc.h>		/* for proc0 declaration */
-#include <sys/protosw.h>
-#include <sys/signalvar.h>
 #include <sys/socket.h>
 #include <sys/socketvar.h>
 #include <sys/sysctl.h>
 #include <sys/syslog.h>
 #include <sys/systm.h>
 
-#include <machine/cpu.h>	/* before tcp_seq.h, for tcp_random18() */
-
 #include <vm/uma.h>
 
 #include <net/if.h>
@@ -62,12 +54,9 @@
 #include <netinet/in_systm.h>
 #include <netinet/in_var.h>
 #include <netinet/ip.h>
-#include <netinet/ip_icmp.h>	/* required for icmp_var.h */
-#include <netinet/icmp_var.h>	/* for ICMP_BANDLIM */
 #include <netinet/ip_var.h>
 #include <netinet/ip_options.h>
 #include <netinet/ip6.h>
-#include <netinet/icmp6.h>
 #include <netinet6/in6_pcb.h>
 #include <netinet6/ip6_var.h>
 #include <netinet6/nd6.h>
@@ -82,21 +71,6 @@
 #include <netinet/tcp_debug.h>
 #endif /* TCPDEBUG */
 
-#ifdef FAST_IPSEC
-#include <netipsec/ipsec.h>
-#include <netipsec/ipsec6.h>
-#endif /*FAST_IPSEC*/
-
-#ifdef IPSEC
-#include <netinet6/ipsec.h>
-#include <netinet6/ipsec6.h>
-#include <netkey/key.h>
-#endif /*IPSEC*/
-
-#include <machine/in_cksum.h>
-
-#include <security/mac/mac_framework.h>
-
 SYSCTL_NODE(_net_inet_tcp, OID_AUTO, reass, CTLFLAG_RW, 0,
     "TCP Segment Reassembly Queue");
 
@@ -120,10 +94,6 @@ SYSCTL_INT(_net_inet_tcp_reass, OID_AUTO, overflows, CTLFLAG_RD,
     &tcp_reass_overflows, 0,
     "Global number of TCP Segment Reassembly Queue Overflows");
 
-static int	 tcp_reass(struct tcpcb *, struct tcphdr *, int *,
-		     struct mbuf *);
-
-
 /* Initialize TCP reassembly queue */
 static void
 tcp_reass_zone_change(void *tag)
@@ -134,6 +104,7 @@ tcp_reass_zone_change(void *tag)
 }
 
 uma_zone_t	tcp_reass_zone;
+
 void
 tcp_reass_init(void)
 {
@@ -148,7 +119,7 @@ tcp_reass_init(void)
 	    tcp_reass_zone_change, NULL, EVENTHANDLER_PRI_ANY);
 }
 
-static int
+int
 tcp_reass(struct tcpcb *tp, struct tcphdr *th, int *tlenp, struct mbuf *m)
 {
 	struct tseg_qent *q;
diff --git a/sys/netinet/tcp_subr.c b/sys/netinet/tcp_subr.c
index 90c2aba..8d2e8e4 100644
--- a/sys/netinet/tcp_subr.c
+++ b/sys/netinet/tcp_subr.c
@@ -162,52 +162,6 @@ static int	tcp_isn_reseed_interval = 0;
 SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_RW,
     &tcp_isn_reseed_interval, 0, "Seconds between reseeding of ISN secret");
 
-static uma_zone_t tcptw_zone;
-static int	maxtcptw;
-
-static int
-tcptw_auto_size(void)
-{
-	int halfrange;
-
-	/*
-	 * Max out at half the ephemeral port range so that TIME_WAIT
-	 * sockets don't tie up too many ephemeral ports.
-	 */
-	if (ipport_lastauto > ipport_firstauto)
-		halfrange = (ipport_lastauto - ipport_firstauto) / 2;
-	else
-		halfrange = (ipport_firstauto - ipport_lastauto) / 2;
-	/* Protect against goofy port ranges smaller than 32. */
-	return (imin(imax(halfrange, 32), maxsockets / 5));
-}
-
-static int
-sysctl_maxtcptw(SYSCTL_HANDLER_ARGS)
-{
-	int error, new;
-
-	if (maxtcptw == 0)
-		new = tcptw_auto_size();
-	else
-		new = maxtcptw;
-	error = sysctl_handle_int(oidp, &new, sizeof(int), req);
-	if (error == 0 && req->newptr)
-		if (new >= 32) {
-			maxtcptw = new;
-			uma_zone_set_max(tcptw_zone, maxtcptw);
-		}
-	return (error);
-}
-SYSCTL_PROC(_net_inet_tcp, OID_AUTO, maxtcptw, CTLTYPE_INT|CTLFLAG_RW,
-    &maxtcptw, 0, sysctl_maxtcptw, "IU",
-    "Maximum number of compressed TCP TIME_WAIT entries");
-
-static int	nolocaltimewait = 0;
-SYSCTL_INT(_net_inet_tcp, OID_AUTO, nolocaltimewait, CTLFLAG_RW,
-    &nolocaltimewait, 0,
-    "Do not create compressed TCP TIME_WAIT entries for local connections");
-
 /*
  * TCP bandwidth limiting sysctls.  Note that the default lower bound of
  * 1024 exists only for debugging.  A good production default would be
@@ -284,8 +238,7 @@ tcp_zone_change(void *tag)
 
 	uma_zone_set_max(tcbinfo.ipi_zone, maxsockets);
 	uma_zone_set_max(tcpcb_zone, maxsockets);
-	if (maxtcptw == 0)
-		uma_zone_set_max(tcptw_zone, tcptw_auto_size());
+	tcp_tw_zone_change();
 }
 
 static int
@@ -345,14 +298,8 @@ tcp_init(void)
 	tcpcb_zone = uma_zcreate("tcpcb", sizeof(struct tcpcb_mem),
 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
 	uma_zone_set_max(tcpcb_zone, maxsockets);
-	tcptw_zone = uma_zcreate("tcptw", sizeof(struct tcptw),
-	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
-	TUNABLE_INT_FETCH("net.inet.tcp.maxtcptw", &maxtcptw);
-	if (maxtcptw == 0)
-		uma_zone_set_max(tcptw_zone, tcptw_auto_size());
-	else
-		uma_zone_set_max(tcptw_zone, maxtcptw);
 	tcp_timer_init();
+	tcp_tw_init();
 	syncache_init();
 	tcp_hc_init();
 	tcp_reass_init();
@@ -1742,303 +1689,6 @@ ipsec_hdrsiz_tcp(struct tcpcb *tp)
 #endif /*IPSEC*/
 
 /*
- * Move a TCP connection into TIME_WAIT state.
- *    tcbinfo is locked.
- *    inp is locked, and is unlocked before returning.
- */
-void
-tcp_twstart(struct tcpcb *tp)
-{
-	struct tcptw *tw;
-	struct inpcb *inp = tp->t_inpcb;
-	int acknow;
-	struct socket *so;
-
-	INP_INFO_WLOCK_ASSERT(&tcbinfo);	/* tcp_timer_2msl_reset(). */
-	INP_LOCK_ASSERT(inp);
-
-	if (nolocaltimewait && in_localip(inp->inp_faddr)) {
-		tp = tcp_close(tp);
-		if (tp != NULL)
-			INP_UNLOCK(inp);
-		return;
-	}
-
-	tw = uma_zalloc(tcptw_zone, M_NOWAIT);
-	if (tw == NULL) {
-		tw = tcp_timer_2msl_tw(1);
-		if (tw == NULL) {
-			tp = tcp_close(tp);
-			if (tp != NULL)
-				INP_UNLOCK(inp);
-			return;
-		}
-	}
-	tw->tw_inpcb = inp;
-
-	/*
-	 * Recover last window size sent.
-	 */
-	tw->last_win = (tp->rcv_adv - tp->rcv_nxt) >> tp->rcv_scale;
-
-	/*
-	 * Set t_recent if timestamps are used on the connection.
-	 */
-	if ((tp->t_flags & (TF_REQ_TSTMP|TF_RCVD_TSTMP|TF_NOOPT)) ==
-	    (TF_REQ_TSTMP|TF_RCVD_TSTMP)) {
-		tw->t_recent = tp->ts_recent;
-		tw->ts_offset = tp->ts_offset;
-	} else {
-		tw->t_recent = 0;
-		tw->ts_offset = 0;
-	}
-
-	tw->snd_nxt = tp->snd_nxt;
-	tw->rcv_nxt = tp->rcv_nxt;
-	tw->iss     = tp->iss;
-	tw->irs     = tp->irs;
-	tw->t_starttime = tp->t_starttime;
-	tw->tw_time = 0;
-
-/* XXX
- * If this code will
- * be used for fin-wait-2 state also, then we may need
- * a ts_recent from the last segment.
- */
-	acknow = tp->t_flags & TF_ACKNOW;
-
-	/*
-	 * First, discard tcpcb state, which includes stopping its timers and
-	 * freeing it.  tcp_discardcb() used to also release the inpcb, but
-	 * that work is now done in the caller.
-	 *
-	 * Note: soisdisconnected() call used to be made in tcp_discardcb(),
-	 * and might not be needed here any longer.
-	 */
-	tcp_discardcb(tp);
-	so = inp->inp_socket;
-	soisdisconnected(so);
-	tw->tw_cred = crhold(so->so_cred);
-	SOCK_LOCK(so);
-	tw->tw_so_options = so->so_options;
-	SOCK_UNLOCK(so);
-	if (acknow)
-		tcp_twrespond(tw, TH_ACK);
-	inp->inp_ppcb = tw;
-	inp->inp_vflag |= INP_TIMEWAIT;
-	tcp_timer_2msl_reset(tw, 0);
-
-	/*
-	 * If the inpcb owns the sole reference to the socket, then we can
-	 * detach and free the socket as it is not needed in time wait.
-	 */
-	if (inp->inp_vflag & INP_SOCKREF) {
-		KASSERT(so->so_state & SS_PROTOREF,
-		    ("tcp_twstart: !SS_PROTOREF"));
-		inp->inp_vflag &= ~INP_SOCKREF;
-		INP_UNLOCK(inp);
-		ACCEPT_LOCK();
-		SOCK_LOCK(so);
-		so->so_state &= ~SS_PROTOREF;
-		sofree(so);
-	} else
-		INP_UNLOCK(inp);
-}
-
-#if 0
-/*
- * The appromixate rate of ISN increase of Microsoft TCP stacks;
- * the actual rate is slightly higher due to the addition of
- * random positive increments.
- *
- * Most other new OSes use semi-randomized ISN values, so we
- * do not need to worry about them.
- */
-#define MS_ISN_BYTES_PER_SECOND		250000
-
-/*
- * Determine if the ISN we will generate has advanced beyond the last
- * sequence number used by the previous connection.  If so, indicate
- * that it is safe to recycle this tw socket by returning 1.
- */
-int
-tcp_twrecycleable(struct tcptw *tw)
-{
-	tcp_seq new_iss = tw->iss;
-	tcp_seq new_irs = tw->irs;
-
-	INP_INFO_WLOCK_ASSERT(&tcbinfo);
-	new_iss += (ticks - tw->t_starttime) * (ISN_BYTES_PER_SECOND / hz);
-	new_irs += (ticks - tw->t_starttime) * (MS_ISN_BYTES_PER_SECOND / hz);
-
-	if (SEQ_GT(new_iss, tw->snd_nxt) && SEQ_GT(new_irs, tw->rcv_nxt))
-		return (1);
-	else
-		return (0);
-}
-#endif
-
-void
-tcp_twclose(struct tcptw *tw, int reuse)
-{
-	struct socket *so;
-	struct inpcb *inp;
-
-	/*
-	 * At this point, we are in one of two situations:
-	 *
-	 * (1) We have no socket, just an inpcb<->twtcp pair.  We can free
-	 *     all state.
-	 *
-	 * (2) We have a socket -- if we own a reference, release it and
-	 *     notify the socket layer.
-	 */
-	inp = tw->tw_inpcb;
-	KASSERT((inp->inp_vflag & INP_TIMEWAIT), ("tcp_twclose: !timewait"));
-	KASSERT(intotw(inp) == tw, ("tcp_twclose: inp_ppcb != tw"));
-	INP_INFO_WLOCK_ASSERT(&tcbinfo);	/* tcp_timer_2msl_stop(). */
-	INP_LOCK_ASSERT(inp);
-
-	tw->tw_inpcb = NULL;
-	tcp_timer_2msl_stop(tw);
-	inp->inp_ppcb = NULL;
-	in_pcbdrop(inp);
-
-	so = inp->inp_socket;
-	if (so != NULL) {
-		/*
-		 * If there's a socket, handle two cases: first, we own a
-		 * strong reference, which we will now release, or we don't
-		 * in which case another reference exists (XXXRW: think
-		 * about this more), and we don't need to take action.
-		 */
-		if (inp->inp_vflag & INP_SOCKREF) {
-			inp->inp_vflag &= ~INP_SOCKREF;
-			INP_UNLOCK(inp);
-			ACCEPT_LOCK();
-			SOCK_LOCK(so);
-			KASSERT(so->so_state & SS_PROTOREF,
-			    ("tcp_twclose: INP_SOCKREF && !SS_PROTOREF"));
-			so->so_state &= ~SS_PROTOREF;
-			sofree(so);
-		} else {
-			/*
-			 * If we don't own the only reference, the socket and
-			 * inpcb need to be left around to be handled by
-			 * tcp_usr_detach() later.
-			 */
-			INP_UNLOCK(inp);
-		}
-	} else {
-#ifdef INET6
-		if (inp->inp_vflag & INP_IPV6PROTO)
-			in6_pcbfree(inp);
-		else
-#endif
-			in_pcbfree(inp);
-	}
-	tcpstat.tcps_closed++;
-	crfree(tw->tw_cred);
-	tw->tw_cred = NULL;
-	if (reuse)
-		return;
-	uma_zfree(tcptw_zone, tw);
-}
-
-int
-tcp_twrespond(struct tcptw *tw, int flags)
-{
-	struct inpcb *inp = tw->tw_inpcb;
-	struct tcphdr *th;
-	struct mbuf *m;
-	struct ip *ip = NULL;
-	u_int hdrlen, optlen;
-	int error;
-	struct tcpopt to;
-#ifdef INET6
-	struct ip6_hdr *ip6 = NULL;
-	int isipv6 = inp->inp_inc.inc_isipv6;
-#endif
-
-	INP_LOCK_ASSERT(inp);
-
-	m = m_gethdr(M_DONTWAIT, MT_DATA);
-	if (m == NULL)
-		return (ENOBUFS);
-	m->m_data += max_linkhdr;
-
-#ifdef MAC
-	mac_create_mbuf_from_inpcb(inp, m);
-#endif
-
-#ifdef INET6
-	if (isipv6) {
-		hdrlen = sizeof(struct ip6_hdr) + sizeof(struct tcphdr);
-		ip6 = mtod(m, struct ip6_hdr *);
-		th = (struct tcphdr *)(ip6 + 1);
-		tcpip_fillheaders(inp, ip6, th);
-	} else
-#endif
-	{
-		hdrlen = sizeof(struct tcpiphdr);
-		ip = mtod(m, struct ip *);
-		th = (struct tcphdr *)(ip + 1);
-		tcpip_fillheaders(inp, ip, th);
-	}
-	to.to_flags = 0;
-
-	/*
-	 * Send a timestamp and echo-reply if both our side and our peer
-	 * have sent timestamps in our SYN's and this is not a RST.
-	 */
-	if (tw->t_recent && flags == TH_ACK) {
-		to.to_flags |= TOF_TS;
-		to.to_tsval = ticks + tw->ts_offset;
-		to.to_tsecr = tw->t_recent;
-	}
-	optlen = tcp_addoptions(&to, (u_char *)(th + 1));
-
-	m->m_len = hdrlen + optlen;
-	m->m_pkthdr.len = m->m_len;
-
-	KASSERT(max_linkhdr + m->m_len <= MHLEN, ("tcptw: mbuf too small"));
-
-	th->th_seq = htonl(tw->snd_nxt);
-	th->th_ack = htonl(tw->rcv_nxt);
-	th->th_off = (sizeof(struct tcphdr) + optlen) >> 2;
-	th->th_flags = flags;
-	th->th_win = htons(tw->last_win);
-
-#ifdef INET6
-	if (isipv6) {
-		th->th_sum = in6_cksum(m, IPPROTO_TCP, sizeof(struct ip6_hdr),
-		    sizeof(struct tcphdr) + optlen);
-		ip6->ip6_hlim = in6_selecthlim(inp, NULL);
-		error = ip6_output(m, inp->in6p_outputopts, NULL,
-		    (tw->tw_so_options & SO_DONTROUTE), NULL, NULL, inp);
-	} else
-#endif
-	{
-		th->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
-		    htons(sizeof(struct tcphdr) + optlen + IPPROTO_TCP));
-		m->m_pkthdr.csum_flags = CSUM_TCP;
-		m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum);
-		ip->ip_len = m->m_pkthdr.len;
-		if (path_mtu_discovery)
-			ip->ip_off |= IP_DF;
-		error = ip_output(m, inp->inp_options, NULL,
-		    ((tw->tw_so_options & SO_DONTROUTE) ? IP_ROUTETOIF : 0),
-		    NULL, inp);
-	}
-	if (flags & TH_ACK)
-		tcpstat.tcps_sndacks++;
-	else
-		tcpstat.tcps_sndctrl++;
-	tcpstat.tcps_sndtotal++;
-	return (error);
-}
-
-/*
  * TCP BANDWIDTH DELAY PRODUCT WINDOW LIMITING
  *
  * This code attempts to calculate the bandwidth-delay product as a
diff --git a/sys/netinet/tcp_timewait.c b/sys/netinet/tcp_timewait.c
index b1e22bc..c04b6fc 100644
--- a/sys/netinet/tcp_timewait.c
+++ b/sys/netinet/tcp_timewait.c
@@ -30,10 +30,8 @@
  * $FreeBSD$
  */
 
-#include "opt_compat.h"
 #include "opt_inet.h"
 #include "opt_inet6.h"
-#include "opt_ipsec.h"
 #include "opt_mac.h"
 #include "opt_tcpdebug.h"
 
@@ -44,9 +42,6 @@
 #include <sys/sysctl.h>
 #include <sys/malloc.h>
 #include <sys/mbuf.h>
-#ifdef INET6
-#include <sys/domain.h>
-#endif
 #include <sys/priv.h>
 #include <sys/proc.h>
 #include <sys/socket.h>
@@ -91,26 +86,7 @@
 #endif
 #include <netinet6/ip6protosw.h>
 
-#ifdef IPSEC
-#include <netinet6/ipsec.h>
-#ifdef INET6
-#include <netinet6/ipsec6.h>
-#endif
-#include <netkey/key.h>
-#endif /*IPSEC*/
-
-#ifdef FAST_IPSEC
-#include <netipsec/ipsec.h>
-#include <netipsec/xform.h>
-#ifdef INET6
-#include <netipsec/ipsec6.h>
-#endif
-#include <netipsec/key.h>
-#define	IPSEC
-#endif /*FAST_IPSEC*/
-
 #include <machine/in_cksum.h>
-#include <sys/md5.h>
 
 #include <security/mac/mac_framework.h>
 
@@ -151,6 +127,7 @@ sysctl_maxtcptw(SYSCTL_HANDLER_ARGS)
 		}
 	return (error);
 }
+
 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, maxtcptw, CTLTYPE_INT|CTLFLAG_RW,
     &maxtcptw, 0, sysctl_maxtcptw, "IU",
     "Maximum number of compressed TCP TIME_WAIT entries");
@@ -160,11 +137,8 @@ SYSCTL_INT(_net_inet_tcp, OID_AUTO, nolocaltimewait, CTLFLAG_RW,
     &nolocaltimewait, 0,
     "Do not create compressed TCP TIME_WAIT entries for local connections");
 
-/*
- * TCP initialization.
- */
-static void
-tcp_zone_change(void *tag)
+void
+tcp_tw_zone_change(void)
 {
 
 	if (maxtcptw == 0)
@@ -172,7 +146,7 @@ tcp_zone_change(void *tag)
 }
 
 void
-tcp_init(void)
+tcp_tw_init(void)
 {
 
 	tcptw_zone = uma_zcreate("tcptw", sizeof(struct tcptw),
diff --git a/sys/netinet/tcp_var.h b/sys/netinet/tcp_var.h
index bb1c18d..925ee7d 100644
--- a/sys/netinet/tcp_var.h
+++ b/sys/netinet/tcp_var.h
@@ -75,6 +75,18 @@ struct tcptemp {
 
 #define tcp6cb		tcpcb  /* for KAME src sync over BSD*'s */
 
+/* Neighbor Discovery, Neighbor Unreachability Detection Upper layer hint. */
+#ifdef INET6
+#define ND6_HINT(tp)						\
+do {								\
+	if ((tp) && (tp)->t_inpcb &&				\
+	    ((tp)->t_inpcb->inp_vflag & INP_IPV6) != 0)		\
+		nd6_nud_hint(NULL, NULL, 0);			\
+} while (0)
+#else
+#define ND6_HINT(tp)
+#endif
+
 /*
  * Tcp control block, one per tcp; fields:
  * Organized for 16 byte cacheline efficiency.
@@ -508,6 +520,7 @@ void	 tcp_drain(void);
 void	 tcp_fasttimo(void);
 void	 tcp_init(void);
 void	 tcp_fini(void *);
+int	 tcp_reass(struct tcpcb *, struct tcphdr *, int *, struct mbuf *);
 void	 tcp_reass_init(void);
 void	 tcp_input(struct mbuf *, int);
 u_long	 tcp_maxmtu(struct in_conninfo *, int *);
@@ -523,6 +536,8 @@ struct tcpcb *
 int	 tcp_output(struct tcpcb *);
 void	 tcp_respond(struct tcpcb *, void *,
 	    struct tcphdr *, struct mbuf *, tcp_seq, tcp_seq, int);
+void	 tcp_tw_init(void);
+void	 tcp_tw_zone_change(void);
 int	 tcp_twrespond(struct tcptw *, int);
 void	 tcp_setpersist(struct tcpcb *);
 #ifdef TCP_SIGNATURE